[PATCH v2 3/7] coresight-tgu: Add signal priority support

From: Songwei Chai
Date: Thu Oct 10 2024 - 04:25:09 EST


Like circuit of a Logic analyzer, in TGU, the requirement could be
configured in each step and the trigger will be created once the
requirements are met. Add priority functionality here to sort the
signals into different priorities. The signal which is wanted could
be configured in each step's priority node, the larger number means
the higher priority and the signal with higher priority will be sensed
more preferentially.

Signed-off-by: Songwei Chai <quic_songchai@xxxxxxxxxxx>
---
.../testing/sysfs-bus-coresight-devices-tgu | 7 +
drivers/hwtracing/coresight/coresight-tgu.c | 139 ++++++++++++++++++
drivers/hwtracing/coresight/coresight-tgu.h | 110 ++++++++++++++
3 files changed, 256 insertions(+)

diff --git a/Documentation/ABI/testing/sysfs-bus-coresight-devices-tgu b/Documentation/ABI/testing/sysfs-bus-coresight-devices-tgu
index ee976b67ff01..599908a88e80 100644
--- a/Documentation/ABI/testing/sysfs-bus-coresight-devices-tgu
+++ b/Documentation/ABI/testing/sysfs-bus-coresight-devices-tgu
@@ -7,3 +7,10 @@ Description:
Accepts only one of the 2 values - 0 or 1.
0 : disable TGU.
1 : enable TGU.
+
+What: /sys/bus/coresight/devices/<tgu-name>/step[0:7]_priority[0:3]/reg[0:17]
+Date: August 2024
+KernelVersion 6.10
+Contact: Jinlong Mao (QUIC) <quic_jinlmao@xxxxxxxxxxx>, Sam Chai (QUIC) <quic_songchai@xxxxxxxxxxx>
+Description:
+ (RW) Set/Get the sensed siganal with specific step and priority for TGU.
diff --git a/drivers/hwtracing/coresight/coresight-tgu.c b/drivers/hwtracing/coresight/coresight-tgu.c
index 1a196c90a973..20244c178586 100644
--- a/drivers/hwtracing/coresight/coresight-tgu.c
+++ b/drivers/hwtracing/coresight/coresight-tgu.c
@@ -17,9 +17,92 @@

DEFINE_CORESIGHT_DEVLIST(tgu_devs, "tgu");

+static int calculate_array_location(struct tgu_drvdata *drvdata, int step_index,
+ int operation_index, int reg_index)
+{
+ int ret = -EINVAL;
+
+ ret = operation_index * (drvdata->max_step) *
+ (drvdata->max_reg) + step_index * (drvdata->max_reg)
+ + reg_index;
+
+ return ret;
+}
+
+static ssize_t tgu_dataset_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct tgu_drvdata *drvdata = dev_get_drvdata(dev->parent);
+ struct tgu_attribute *tgu_attr =
+ container_of(attr, struct tgu_attribute, attr);
+
+ return sysfs_emit(buf, "0x%x\n",
+ drvdata->value_table->priority[calculate_array_location(
+ drvdata, tgu_attr->step_index,
+ tgu_attr->operation_index, tgu_attr->reg_num)]);
+
+}
+
+static ssize_t tgu_dataset_store(struct device *dev,
+ struct device_attribute *attr, const char *buf,
+ size_t size)
+{
+ unsigned long val;
+ ssize_t ret = -EINVAL;
+
+ struct tgu_drvdata *tgu_drvdata = dev_get_drvdata(dev->parent);
+ struct tgu_attribute *tgu_attr =
+ container_of(attr, struct tgu_attribute, attr);
+
+ if (kstrtoul(buf, 0, &val))
+ return ret;
+
+ guard(spinlock)(&tgu_drvdata->spinlock);
+ tgu_drvdata->value_table->priority[calculate_array_location(
+ tgu_drvdata, tgu_attr->step_index, tgu_attr->operation_index,
+ tgu_attr->reg_num)] = val;
+ ret = size;
+
+ return ret;
+}
+
+static umode_t tgu_node_visible(struct kobject *kobject, struct attribute *attr,
+ int n)
+{
+ struct device *dev = kobj_to_dev(kobject);
+ struct tgu_drvdata *drvdata = dev_get_drvdata(dev->parent);
+ int ret = 0;
+
+ struct device_attribute *dev_attr =
+ container_of(attr, struct device_attribute, attr);
+ struct tgu_attribute *tgu_attr =
+ container_of(dev_attr, struct tgu_attribute, attr);
+
+ if (tgu_attr->step_index < drvdata->max_step) {
+ ret = (tgu_attr->reg_num < drvdata->max_reg) ?
+ attr->mode : 0;
+ return ret;
+ }
+ return SYSFS_GROUP_INVISIBLE;
+}
+
static void tgu_write_all_hw_regs(struct tgu_drvdata *drvdata)
{
+ int i, j, k;
+
CS_UNLOCK(drvdata->base);
+
+ for (i = 0; i < drvdata->max_step; i++) {
+ for (j = 0; j < MAX_PRIORITY; j++) {
+ for (k = 0; k < drvdata->max_reg; k++) {
+ tgu_writel(drvdata,
+ drvdata->value_table->priority
+ [calculate_array_location(drvdata, i, j, k)],
+ PRIORITY_REG_STEP(i, j, k));
+ }
+ }
+ }
+
/* Enable TGU to program the triggers */
tgu_writel(drvdata, 1, TGU_CONTROL);
CS_LOCK(drvdata->base);
@@ -130,6 +213,38 @@ static const struct attribute_group tgu_common_grp = {

static const struct attribute_group *tgu_attr_groups[] = {
&tgu_common_grp,
+ PRIORITY_ATTRIBUTE_GROUP_INIT(0, 0),
+ PRIORITY_ATTRIBUTE_GROUP_INIT(0, 1),
+ PRIORITY_ATTRIBUTE_GROUP_INIT(0, 2),
+ PRIORITY_ATTRIBUTE_GROUP_INIT(0, 3),
+ PRIORITY_ATTRIBUTE_GROUP_INIT(1, 0),
+ PRIORITY_ATTRIBUTE_GROUP_INIT(1, 1),
+ PRIORITY_ATTRIBUTE_GROUP_INIT(1, 2),
+ PRIORITY_ATTRIBUTE_GROUP_INIT(1, 3),
+ PRIORITY_ATTRIBUTE_GROUP_INIT(2, 0),
+ PRIORITY_ATTRIBUTE_GROUP_INIT(2, 1),
+ PRIORITY_ATTRIBUTE_GROUP_INIT(2, 2),
+ PRIORITY_ATTRIBUTE_GROUP_INIT(2, 3),
+ PRIORITY_ATTRIBUTE_GROUP_INIT(3, 0),
+ PRIORITY_ATTRIBUTE_GROUP_INIT(3, 1),
+ PRIORITY_ATTRIBUTE_GROUP_INIT(3, 2),
+ PRIORITY_ATTRIBUTE_GROUP_INIT(3, 3),
+ PRIORITY_ATTRIBUTE_GROUP_INIT(4, 0),
+ PRIORITY_ATTRIBUTE_GROUP_INIT(4, 1),
+ PRIORITY_ATTRIBUTE_GROUP_INIT(4, 2),
+ PRIORITY_ATTRIBUTE_GROUP_INIT(4, 3),
+ PRIORITY_ATTRIBUTE_GROUP_INIT(5, 0),
+ PRIORITY_ATTRIBUTE_GROUP_INIT(5, 1),
+ PRIORITY_ATTRIBUTE_GROUP_INIT(5, 2),
+ PRIORITY_ATTRIBUTE_GROUP_INIT(5, 3),
+ PRIORITY_ATTRIBUTE_GROUP_INIT(6, 0),
+ PRIORITY_ATTRIBUTE_GROUP_INIT(6, 1),
+ PRIORITY_ATTRIBUTE_GROUP_INIT(6, 2),
+ PRIORITY_ATTRIBUTE_GROUP_INIT(6, 3),
+ PRIORITY_ATTRIBUTE_GROUP_INIT(7, 0),
+ PRIORITY_ATTRIBUTE_GROUP_INIT(7, 1),
+ PRIORITY_ATTRIBUTE_GROUP_INIT(7, 2),
+ PRIORITY_ATTRIBUTE_GROUP_INIT(7, 3),
NULL,
};

@@ -164,6 +279,30 @@ static int tgu_probe(struct amba_device *adev, const struct amba_id *id)

spin_lock_init(&drvdata->spinlock);

+ ret = of_property_read_u32(adev->dev.of_node, "tgu-regs",
+ &drvdata->max_reg);
+ if (ret)
+ return -EINVAL;
+
+ ret = of_property_read_u32(adev->dev.of_node, "tgu-steps",
+ &drvdata->max_step);
+ if (ret)
+ return -EINVAL;
+
+ drvdata->value_table =
+ devm_kzalloc(dev, sizeof(*drvdata->value_table), GFP_KERNEL);
+ if (!drvdata->value_table)
+ return -ENOMEM;
+
+ drvdata->value_table->priority = devm_kzalloc(
+ dev,
+ MAX_PRIORITY * drvdata->max_reg * drvdata->max_step *
+ sizeof(*(drvdata->value_table->priority)),
+ GFP_KERNEL);
+
+ if (!drvdata->value_table->priority)
+ return -ENOMEM;
+
drvdata->enable = false;
desc.type = CORESIGHT_DEV_TYPE_HELPER;
desc.pdata = adev->dev.platform_data;
diff --git a/drivers/hwtracing/coresight/coresight-tgu.h b/drivers/hwtracing/coresight/coresight-tgu.h
index 6e793421066b..8d7ea0516ad1 100644
--- a/drivers/hwtracing/coresight/coresight-tgu.h
+++ b/drivers/hwtracing/coresight/coresight-tgu.h
@@ -13,6 +13,110 @@
#define tgu_writel(drvdata, val, off) __raw_writel((val), drvdata->base + off)
#define tgu_readl(drvdata, off) __raw_readl(drvdata->base + off)

+/*
+ * TGU configuration space Step configuration
+ * offset table space layout
+ * x-------------------------x$ x-------------x$
+ * | |$ | |$
+ * | | | reserve |$
+ * | | | |$
+ * |coresight management | |-------------|base+n*0x1D8+0x1F4$
+ * | registe | |---> |prioroty[3] |$
+ * | | | |-------------|base+n*0x1D8+0x194$
+ * | | | |prioroty[2] |$
+ * |-------------------------| | |-------------|base+n*0x1D8+0x134$
+ * | | | |prioroty[1] |$
+ * | step[7] | | |-------------|base+n*0x1D8+0xD4$
+ * |-------------------------|->base+0x40+7*0x1D8 | |prioroty[0] |$
+ * | | | |-------------|base+n*0x1D8+0x74$
+ * | ... | | | condition |$
+ * | | | | select |$
+ * |-------------------------|->base+0x40+1*0x1D8 | |-------------|base+n*0x1D8+0x60$
+ * | | | | condition |$
+ * | step[0] |--------------------> | decode |$
+ * |-------------------------|-> base+0x40 |-------------|base+n*0x1D8+0x50$
+ * | | | |$
+ * | Control and status space| |Timer/Counter|$
+ * | space | | |$
+ * x-------------------------x->base x-------------x base+n*0x1D8+0x40$
+ *
+ */
+
+/* Calculate compare step addresses */
+#define PRIORITY_REG_STEP(step, priority, reg)\
+ (0x0074 + 0x60 * priority + 0x4 * reg + 0x1D8 * step)
+
+#define tgu_dataset_ro(name, step_index, type, reg_num) \
+ (&((struct tgu_attribute[]){ { \
+ __ATTR(name, 0444, tgu_dataset_show, NULL), \
+ step_index, \
+ type, \
+ reg_num, \
+ } })[0].attr.attr)
+
+#define tgu_dataset_rw(name, step_index, type, reg_num) \
+ (&((struct tgu_attribute[]){ { \
+ __ATTR(name, 0644, tgu_dataset_show, tgu_dataset_store), \
+ step_index, \
+ type, \
+ reg_num, \
+ } })[0].attr.attr)
+
+#define STEP_PRIORITY(step_index, reg_num, priority) \
+ tgu_dataset_rw(reg##reg_num, step_index, TGU_PRIORITY##priority, \
+ reg_num)
+
+#define STEP_PRIORITY_LIST(step_index, priority) \
+ {STEP_PRIORITY(step_index, 0, priority), \
+ STEP_PRIORITY(step_index, 1, priority), \
+ STEP_PRIORITY(step_index, 2, priority), \
+ STEP_PRIORITY(step_index, 3, priority), \
+ STEP_PRIORITY(step_index, 4, priority), \
+ STEP_PRIORITY(step_index, 5, priority), \
+ STEP_PRIORITY(step_index, 6, priority), \
+ STEP_PRIORITY(step_index, 7, priority), \
+ STEP_PRIORITY(step_index, 8, priority), \
+ STEP_PRIORITY(step_index, 9, priority), \
+ STEP_PRIORITY(step_index, 10, priority), \
+ STEP_PRIORITY(step_index, 11, priority), \
+ STEP_PRIORITY(step_index, 12, priority), \
+ STEP_PRIORITY(step_index, 13, priority), \
+ STEP_PRIORITY(step_index, 14, priority), \
+ STEP_PRIORITY(step_index, 15, priority), \
+ STEP_PRIORITY(step_index, 16, priority), \
+ STEP_PRIORITY(step_index, 17, priority), \
+ NULL \
+ }
+
+#define PRIORITY_ATTRIBUTE_GROUP_INIT(step, priority)\
+ (&(const struct attribute_group){\
+ .attrs = (struct attribute*[])STEP_PRIORITY_LIST(step, priority),\
+ .is_visible = tgu_node_visible,\
+ .name = "step" #step "_priority" #priority \
+ })
+
+enum operation_index {
+ TGU_PRIORITY0,
+ TGU_PRIORITY1,
+ TGU_PRIORITY2,
+ TGU_PRIORITY3
+
+};
+
+/* Maximum priority that TGU supports */
+#define MAX_PRIORITY 4
+
+struct tgu_attribute {
+ struct device_attribute attr;
+ u32 step_index;
+ enum operation_index operation_index;
+ u32 reg_num;
+};
+
+struct value_table {
+ unsigned int *priority;
+};
+
/**
* struct tgu_drvdata - Data structure for a TGU (Trigger Generator Unit) device
* @base: Memory-mapped base address of the TGU device
@@ -20,6 +124,9 @@
* @csdev: Pointer to the associated coresight device
* @spinlock: Spinlock for handling concurrent access
* @enable: Flag indicating whether the TGU device is enabled
+ * @value_table: Store given value based on relevant parameters.
+ * @max_reg: Maximum number of registers
+ * @max_step: Maximum step size
*
* This structure defines the data associated with a TGU device, including its base
* address, device pointers, clock, spinlock for synchronization, trigger data pointers,
@@ -31,6 +138,9 @@ struct tgu_drvdata {
struct coresight_device *csdev;
spinlock_t spinlock;
bool enable;
+ struct value_table *value_table;
+ int max_reg;
+ int max_step;
};

#endif